A dominant 9th · Piano
A9 Chord on Piano
The A9 chord (A dominant 9th) is built from the notes A, C#, E, G and B. The keyboard diagram below shows exactly which keys to press.
Chord diagrams
Notes in this chord
- A
- C♯
- E
- G
- B
Degrees: 1 – 3 – 5 – ♭7 – 9
How to play
To play A9 on piano, press A, C#, E, G and B together. In root position the lowest note is A, and the finger numbers follow the keys left to right in the diagram.
Theory behind the chord
Dominant ninth chords extend the dominant seventh with a ninth on top. They keep the pull of a seventh chord but sound fuller and more coloured, which is why funk and soul rhythm parts lean on them. On A9 this structure sits on the root A, so the degrees 1 – 3 – 5 – ♭7 – 9 map onto A, C#, E, G and B.
Frequently asked questions
- Which notes are in the A9 chord?
- A9 contains the notes A, C#, E, G and B. Relative to the root these are the degrees 1 – 3 – 5 – ♭7 – 9.
Practise A9 on your phone
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